Background: Identification of an individual is a pre-requisite for certification of death and for personal, social and legal reasons. The study of lip-prints (cheiloscopy) was thought of as a method of identification of a person. It is safe to assume that cheiloscopy, in its present stage of development, has become a means of criminalistic identification dealing with lip-prints. Objective: The objective of the study was to check for any peculiar lip patterns in relation to the sex of the individual and determine the most common lip patterns in the Indian population. Materials and Methods: This study was conducted on 140 subjects, which included 70 males and 70 females, in the age group of 0-70 years. After applying lip stick evenly, the lip-print of each subject was obtained on a simple bond paper by researcher number 1. The lip-print was then analyzed and interpreted by researcher number 2 to determine the sex of individuals. Results: We found that 67 of the actual 70 lip-prints of females were correctly identified and 65 of the 70 males were correctly diagnosed as males. Type C (47.14%) was the most commonly occurring trend in females whereas Type B (70%) was the most commonly occurring trend in males. Conclusion: Along with other traditional methods, cheiloscopy can also serve as very important tool in the identification of a person based on the characteristic arrangement of lines appearing on the red part of the lips.

Background: Rugae are anatomical folds or wrinkles, the irregular fibrous connective tissue located on the anterior third of the palate, behind the incisive papilla. They are also called 'plica palatine.' These rugae patterns are studied for various purposes, mainly in the fields of anthropology, genetics, orthodontics, prosthodontics, and forensic science. Objective: To determine the stability of the palatal rugae during fixed orthodontic treatment and to verify the accuracy rate of identification by comparing the rugae patterns on preoperative and postoperative orthodontic casts. Materials and Methods: Thirty preoperative and postoperative dental casts were selected. Thirty casts were randomly selected for the present study. The postoperative and the randomly selected casts were trimmed so that all areas except the rugae area of the hard palate were removed. The 30 postoperative casts were mixed with the 30 randomly selected casts. Thirteen examiners were selected as evaluators. They were instructed to match the 30 preoperative dental casts with the 60 dental casts (30 postoperative and 30 randomly selected casts). The case numbers of those that were correctly matched were noted. Results: During fixed orthodontic treatment, dental changes and sometimes bony changes occurred, but no changes occurred in the rugae pattern. The 13 examiners achieved 90% correct matches, which is the median in the present study. We used kappa statistics to assess the agreement between evaluators for matching preoperative with postoperative casts. Conclusion: Palatal rugae patterns are unique to an individual, and can therefore be used for individual identification in forensic odontology.

Background: Cementum is a hard tissue in the root, which is deposited around dentin in layers throughout life. Under the light microscope, root cementum is seen as alternate light and dark rings known as incremental lines of cementum. In paleontology and forensic medicine, the number of these incremental lines is used to derive the age at death of an individual. Objectives: The present study was undertaken to determine if any relation exists between incremental lines of cementum and age of the individual. Materials and Methods: Twenty-five teeth from patients of known ages and devoid of any pathology such as attrition or hypercementosis were selected for this study. Ground sections were prepared manually. Nineteen of them showed visible countable annulations, while six showed indistinct, invisible annulations and hence were excluded from the study. Half of the selected teeth were sectioned longitudinally and the remainder were cross-sectioned. The mid-root region was selected for counting the annulations. Cemental annulations were counted after taking a photograph and enlarging the mid-root area. Age was then determined by adding the eruption age of the tooth to the annulations counted. Results and Conclusions: It was observed that cemental annulations, when appreciated, can be used as a reliable guide to determine the age of the patient. The age thus determined varied by about 2−3 years from the actual age of the patient. The reliability of the method was found to be 94.73%. There was good interobserver agreement in counting annulations.

Background: Bucco-lingual (B-L) dimensions of permanent teeth are known to exhibit sexual dimorphism. Objectives: Sexual dimorphism of B-L dimensions is known to be population specific. This study involves the measurement of B-L dimensions of all teeth except third molars of 99 native residents of Mysore district, Karnataka in the age group of 19-30 years. Materials and Methods: The B-L dimensional measurements of 28 teeth, except third molars, of 50 males and 49 females in the age group of 19 to 30 years were made on the study casts using vernier calipers with a resolution of 0.02 mm. The distance between the highest points on the buccal / labial and lingual / palatal surfaces were measured and analyzed using discriminant function analysis. Results: Males showed greater B-L dimensions of teeth in comparison to females with eight maxillary teeth exhibiting statistically significant dimorphism. However, discriminant function analysis showed an overall accuracy of classification of sex of 78%, among which 11 showed maximum dimorphism with a classification accuracy of 70.7% whereas both 23 and 26 showed an accuracy of 66.7%. Conclusion: Application of B-L dimensional variability among males and females in the population of Mysore can aid in sex determination in forensic scenario as the results of this study showed moderate magnitude of dimorphism in maxillary teeth with an accuracy rate of 78%. However, it is recommended to take this odontometric trait into consideration in combination with other skeletal and/or dental traits for sex determination.

Background: The nature of crime is changing day by day and the forensic scientist is always facing new problems in the process of identification. For example, difficult though it may be to believe, criminals are now-a-days using acids to destroy bodies in order to avoid any personal identification. This is a matter of great interest to the forensic scientist. Is it possible to destroy the human body completely in an acid? If so, are there any means to identify the body? Objectives: The aim of this study was to identify the agent (acid) that is most likely to be used in such crimes and to find out if the morphological changes in the teeth could be used to deduce the approximate duration of time elapsed after immersion of a body in an acid. Since the natural teeth are most resistant to destruction they can persist for long after other skeletal structures have been destroyed by physical agents. The objective of study was to observe the morphological changes occurring in natural human teeth when they were kept immersed in an acid solution. Materials and Methods: Teeth were kept in 25 ml of aqueous solutions of three different acids and observed periodically for morphological changes. Results: The results showed that teeth could be completely dissolved in 37% hydrochloric acid (HCl) after 15 h of immersion, whereas in 65% nitric acid 20 h was required for complete dissolution. In the case of 96% sulphuric acid, the teeth reacted in a different manner. There was a residual precipitate observed at the bottom of the container after 144 h. It was possible to identify the characteristic morphological changes in the tooth until an advanced stage of degradation. Conclusion: Hydrochloric acid, nitric acid and sulfuric acid cause changes in the teeth and it is possible to deduce the approximate duration for which a body has been immersed in acid based on the charges observed.

Estimation of age based on tooth cementum annulations using three different microscopic methodsSiddharth Pundir, Susmita Saxena, Pooja AggrawalJuly-December 2009, 1(2):82-87DOI:10.4103/0974-2948.60379

Background: The hard tissues of human dentition are able to resist decay and degradation long after other tissues are lost. This resistance to decay has made teeth useful for calculation of age at death of an individual. Recent research indicates that tooth cementum annulations (TCA) may be used more reliably than other morphological or histological traits of the adult skeleton for estimation of age. Objectives: The purpose of this study was to examine the correlation between age and the number of incremental lines in human dental cementum and to ascertain which, among three different forms of microscopy (light, polarized, phase-contrast) was the most reliable method of studying cementum. Materials and Methods: The study sample consisted of 40 teeth that had been extracted from patients ranging in age from 20−70 years. Longitudinal ground sections of each tooth were prepared and examined under light microscopy, polarized microscopy, and phase-contrast microscopy. The images were magnified on a computer and the cemental lines were counted with the help of Image Analysis Pro 6.0 software. Only the dark lines were counted. Results: There was a strong positive correlation between the estimated age and calculated age when phase-contrast microscopy was used; the correlation was less for light and polarized microscopy. Our results suggest that there is no significant influence of sex, age, periodontal disease, or tooth type on age estimation by the TCA method. This suggests that the accuracy and repeatability of the method is not dependent on tooth type or location and that this method can be applied to the general population regardless of systemic or periodontal health. Conclusion: With this study we conclude that among the methods of counting incremental lines by various types of microscopy phase-contrast microscopy improves the accuracy of age estimation and may serve as a valuable aid in forensic identification.

Background: Death is an irreversible cessation of circulation, respiration and cerebral function. A number of continuous changes occur in the period after death, and these vary according to the duration of time interval and circumstances of death. Since the rate of post-mortem changes varies between different individuals and there exists a range of normal values during life, extrapolation of the time since death will always reveal an interval, not an exact time point at which death occurred. Objectives: This study was conducted to demonstrate the features of decomposition at the cellular level in post-mortem gingival tissues at different time intervals after death and observe the cellular changes in the unfixed ante-mortem gingival tissue at regular time intervals. Materials and Methods: Thirty post-mortem and 30 ante-mortem gingival samples were seen microscopically to observe the cytoplasmic and nuclear degenerative changes. The proportion of cells exhibiting nuclear and cytoplasmic alterations in post-mortem gingival samples, during different time intervals, were compared using Chi square test. Results and Conclusion: There was a significant association between the time intervals and degenerative changes. The initiation of the decomposition process at the cellular level begins within 10 hours after death and the other clinical features of decomposition occur subsequently.

Background: While bitemarks are categorical identification evidence, the dynamics of biting, the anatomical location of the bite, and failures in wound records can introduce distorted images and mislead crime investigation. Materials and Methods: In this study, 20 bitemarks were performed on dead pig skin and subsequently photographed, excised, conserved, and analyzed using digital comparison (Adobe Photoshop™ 8.0), following the standard procedures (ABFO); physical comparison was also done using polyether (Impregum™; 3M) casts. Study plaster casts of the upper and lower jaws of each subject were taken using type IV yellow densite stone. Polyether was used as impression material to obtain bitemarks, and casts were made from densite stone and polyether. Results: Because of its elasticity, polyether casts can compensate for primary or secondary distortions, so that there is a better degree of match when positioning the subject's dental cast. Conclusion: Polyether is an alternative impression material and is an excellent option for creating positive casts of the wound for physical dynamic comparison.

Objectives: The objective of this study was to find out if exposure since birth to a naturally fluoridated drinking water supply has any impact on sexual dimorphism as assessed by measurement of the mandibular canine index. Materials and Methods: Children from two areas were selected for the study: Aaspur (Dungarpur) and Chikhalwas (Udaipur), which are high-fluoride (4.0 ppm) and optimal-fluoride (1.1 ppm) areas, respectively. Data were obtained from 145 school children in the 14-15 year age-group. Of these, 75 were from the high-fluoride area and 70 were from the optimal-fluoride area. Alginate impressions of the mandibular arch were made for all subjects and these were poured immediately in type IV dental stone to minimize dimensional shrinkage. The parameters considered were canine width, intercanine distance, and mandibular canine index. All the measurements were recorded using a modified vernier calipers and divider. Data were statistically analyzed using SPSS/PC+ (SPSS Inc., Illinois, USA). Results: Significant differences were found between optimum-fluoride and high-fluoride areas in all the considered parameters except for the right canine width and the intercanine distance. Standard mandibular canine index is a quick and easy method for determining sex. Conclusion: Fluoride level does not have any particular impact on assessment of sexual dimorphism using the mandibular canine index.